Expanded gas turbine process with natural gas regasification

Patent metadata

Field	Value
Publication number	US-11274598-B2
Application number	US-201916972765-A
Country	US
Kind code	B2
Filing date	Jun 21, 2019
Priority date	Jul 5, 2018
Publication date	Mar 15, 2022
Grant date	Mar 15, 2022

Abstract

A power plant with a multi-stage intercooled compressor, a combustion chamber, a turbine which is arranged downstream of the combustion chamber, a compressor air line which connects the compressor to the combustion chamber, and a first heat exchanger which is connected into the compressor air line and into an exhaust gas line branching off from the turbine. A first compressor air expander is arranged in the compressor air line between the first heat exchanger and the combustion chamber, and the power plant includes a device for regasifying liquid natural gas, having a natural gas line, wherein a heat exchanger device is connected into the natural gas line between two compressor stages of the compressor.

First claim

The invention claimed is:

1. A power station plant comprising:
a multistage compressor with intermediate cooling,
a combustion chamber,
a turbine located downstream of the combustion chamber,
a compressor air conduit which connects the multistage compressor to the combustion chamber and a first heat exchanger installed in the compressor air conduit and in an exhaust gas conduit branching off from the turbine,
wherein the power station plant comprises a device for regasifying liquid natural gas having a natural gas conduit,
wherein a heat transfer device is installed between two compressor stages of the multistage compressor and in the natural gas conduit,
wherein a first compressor air expander is arranged in the compressor air conduit between the first heat exchanger and the combustion chamber,
wherein the heat transfer device comprises a nitrogen circuit comprising a nitrogen conduit in which a third heat exchanger is installed between the two compressor stages and a fourth heat exchanger is installed in the natural gas conduit, and
wherein the nitrogen circuit comprises a fifth heat exchanger which is firstly installed in the nitrogen conduit downstream, in a directional flow of nitrogen in the nitrogen conduit, of the third heat exchanger and upstream of the fourth heat exchanger and is secondly installed in the exhaust gas conduit.

2. The power station plant as claimed in claim 1 ,
wherein the heat transfer device comprises a second heat exchanger which is installed between a pair of adjacent compressor stages of the multistage compressor, wherein the second heat exchanger is separated from the third heat exchanger by at least one compressor stage that is part of the pair of adjacent compressor stages and part of the two compressor stages.

3. The power station plant as claimed in claim 1 ,
wherein a natural gas expander is installed in the natural gas conduit downstream, in a flow direction of the natural gas, of the heat transfer device.

4. The power station plant as claimed in claim 3 ,
wherein a sixth heat exchanger is arranged in the natural gas conduit upstream of the natural gas expander and a seventh heat exchanger is arranged in the natural gas conduit downstream of the natural gas expander in order to heat the natural gas before and after expansion.

5. The power station plant as claimed in claim 3 ,
wherein a twelfth heat exchanger is installed in the natural gas conduit between the heat transfer device and the natural gas expander and in the exhaust gas conduit.

6. The power station plant as claimed in claim 1 , further comprising:
a water-glycol circuit having an eighth heat exchanger in a compressor intake air conduit for cooling and drying compressor intake air or a ninth heat exchanger between the two compressor stages for cooling and drying compressor air, and having a tenth heat exchanger which is installed in the compressor air conduit downstream of the multistage compressor for heating the compressor air, an eleventh heat exchanger for further heating of regasified natural gas from regasifying the liquid natural gas and a twelfth heat exchanger for heating a water-glycol mixture in the water-glycol circuit.

7. The power station plant as claimed in claim 1 ,
wherein a second compressor air expander is arranged downstream of the first compressor air expander and is connected on an inlet side to the compressor air conduit at a position downstream of the first compressor air expander and at an outlet side opens into the exhaust gas conduit.

8. A method for operating a power station plant, the method comprising:
regasifying liquid natural gas using heat arising in compression of compressor air,
selecting an exit pressure of a multistage compressor so as to be higher than a required turbine entry pressure and in which the compressor air is expanded before combustion,
wherein the power station plant comprises:
the multistage compressor with intermediate cooling,
a combustion chamber,
a turbine located downstream of the combustion chamber,
a compressor air conduit which connects the multistage compressor to the combustion chamber and a first heat exchanger installed in the compressor air conduit and in an exhaust gas conduit branching off from the turbine,
wherein the power station plant comprises a device for regasifying the liquid natural gas having a natural gas conduit,
wherein a heat transfer device is installed between two compressor stages of the multistage compressor and in the natural gas conduit,
wherein a first compressor air expander is arranged in the compressor air conduit between the first heat exchanger and the combustion chamber,
wherein the heat transfer device comprises a nitrogen circuit comprising a nitrogen conduit in which a third heat exchanger is installed between the two compressor stages and a fourth heat exchanger is installed in the natural gas conduit, and
wherein the nitrogen circuit comprises a fifth heat exchanger which is firstly installed in the nitrogen conduit downstream, in a directional flow of nitrogen in the nitrogen conduit, of the third heat exchanger and upstream of the fourth heat exchanger and is secondly installed in the exhaust gas conduit.

9. The method as claimed in claim 8 ,
wherein the liquid natural gas is brought to pressure, regasified and subsequently expanded to produce energy.

10. The method as claimed in claim 9 ,
wherein regasified natural gas from regasifying the liquid natural gas is heated by a first further heat source before being expanded to produce the energy and the regasified natural gas is heated by means of a second further heat source after being expanded to produce the energy.

11. The method as claimed in claim 8 ,
wherein compressor intake air is cooled and dried by a water-glycol circuit.

12. A power station plant comprising:
a multistage compressor with intermediate cooling,
a combustion chamber,
a turbine located downstream of the combustion chamber,
a compressor air conduit which connects the multistage compressor to the combustion chamber and a first heat exchanger installed in the compressor air conduit and in an exhaust gas conduit branching off from the turbine,
wherein the power station plant comprises a device for regasifying liquid natural gas comprising a natural gas conduit,
wherein a heat transfer device is installed between two compressor stages of the multistage compressor and in the natural gas conduit,
wherein a first compressor air expander is arranged in the compressor air conduit between the first heat exchanger and the combustion chamber, and
wherein the power station plant further comprises a water-glycol circuit comprising an eighth heat exchanger in a compressor intake air conduit for cooling and drying compressor intake air or a ninth heat exchanger between the two compressor stages for cooling and drying compressor air, and comprising a tenth heat exchanger which is installed in the compressor air conduit downstream of the multistage compressor for heating the compressor air, an eleventh heat exchanger for further heating of regasified natural gas from regasifying the liquid natural gas and a twelfth heat exchanger for heating a water-glycol mixture in the water-glycol circuit.

Assignees

• Siemens Ag

Inventors

• Graeber Carsten
• Juretzek Uwe

Classifications

• F05D2260/207

  using a phase changing mass, e.g. heat absorbing by melting or boiling · CPC title

• F02C7/08 Primary

  Heating air supply before combustion, e.g. by exhaust gases · CPC title

• F05D2260/20

  Heat transfer, e.g. cooling · CPC title

• F02C7/12

  Cooling of plants (of component parts, see the relevant subclasses, e.g. F01D; cooling of engines in general F01P) · CPC title

• F02C3/04 Primary

  having a turbine driving a compressor (power transmission arrangements F02C7/36; control of working fluid flow F02C9/16) · CPC title